Development of Motion Control Systems for Hydraulically Actuated Cranes with Hanging Loads
The newly developed control system has enabled automation and in practice turned the crane into a hydraulic robot.
Konrad Johan Jensen
PhD Candidate
You may follow the disputation online or on campus. Link for registration as an online spectator at the bottom of this page.
Konrad Johan Jensen of the Faculty of and Sciences at the University of Agder has submitted his thesis entitled «Development of Motion Control Systems for Hydraulically Actuated Cranes with Hanging Loads» and will defend the thesis for the PhD-degree Tuesday 28 February 2023.
He has followed the PhD programme in Engineering and Science at UiA, with with Specialisation in Engineering Sciences, scientific field Mechatronics.
Summary of the thesis by Konrad Johan Jensen:
Path control enables automation and robotization of hydraulic cranes
Automation has long been used in industry to increase productivity and safety. The use of robots is a good example of this, but they often have limited lifting capacity.
For heavier lifts both on land and at sea, hydraulic cranes are often used. These are usually manually operated, providing the opportunity to examine and develop control systems for increased automation.
This is one of the main themes in the thesis, where path control for hydraulic cranes has been developed. This makes it possible for the crane to move on its own without an operator, based on commands received. The newly developed control system has enabled automation and in practice turned the crane into a hydraulic robot. Analysis of this control system has been performed using simulation tools and verified with experimental work.
New control systems increase safety during lifting of suspended loads
Cranes often use a winch and wire rope to lift heavy loads. This causes the load to hang as a pendulum from the crane's tip, and in the worst case can cause large swings that can lead to collisions with the surroundings.
A new control system has been developed to compensate for this motion, where the crane tip is actively controlled to reduce the pendulum motion of the suspended load.
In addition, lifting heavy loads causes deflection and oscillations in the crane's mechanical structure, which can become a safety hazard. Measurements have been taken of a crane with and without load to analyze how the crane's mechanical structure is affected by a heavy load. A new control system has been developed that can counteract the deflection and reduce the oscillations in the crane.
Disputation facts:
The trial lecture and the public defence will take place on campus in Auditorium C2 040, Campus Grimstad, and online via the Zoom conferencing app - registration link below.
Head of the Department of Engineering Sciences Paul Ragnar Svennevig, Faculty of Engineering and Science, University of Agder, will chair the disputation.
The trial lecture Tuesday 28 February at 10:15 hours
Public defense Tuesday 28 February at 12:15 hours
Given topic for trial lecture: «Electro-mechanical and hydraulic actuation of large robotic systems -main principles and pros and cons»
Thesis Title: «Development of Motion Control Systems for Hydraulically Actuated Cranes with Hanging Loads»
Search for the thesis in AURA - Agder University Research Archive, a digital archive of scientific papers, theses and dissertations from the academic staff and students at the University of Agder.
The thesis is available here:
https://hdl.handle.net/11250/3044214
The Candidate: Konrad Johan Jensen (1991, Lier) Bachelor of Renewable Energy at UiA (2013), Master of Mechatronics at UiA (2015). He has worked part time at the crane and winch department at National Oilwell Varco (2013-2015). He is currently working as a development engineer at Oceaneering Rotator at Nodeland, Songdalen i Kristiansand.
Opponents:
First opponent: Prof.-Dr. em. Rudolf Scheidl, Johannes Kepler Universitet, Linz, Austria
Second opponent: Associate Professor Anders Hedegaard Hansen, Aalborg University, Denmark
Associate Professor Margrethe Wold, Faculty of Engineering and Science, University of Agder, is appointed as the administrator for the assessment committee.
Supervisors in the doctoral work were Associate Professor Morten Kjeld Ebbesen, University of Agder (main supervisor) and Professor Michael Rygaard Hansen, University of Agder (co-supervisor)
What to do as an online audience member:
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https://uiano.zoom.us/j/68279045775?pwd=R1JRaTBXWitBQXNLelBneHFLSzVhZz09
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Opponent ex auditorio:
The chair invites members of the public to pose questions ex auditorio in the introduction to the public defense. Deadline is during the break between the two opponents. The person asking questions should have read the thesis. For online audience the Contact Persons e-mail are available in the chat function during the Public Defense, and questions ex auditorio can be submitted to Emma Elisabeth Horneman at e-mail emma.e.horneman@uia.no